In this work, thermodynamic efficiency of individual cell and stack of cells (two cells) has been computed by studying the variation of voltage produced during an operation time of 30 min as a result of the affected parameters:- stoichiometric feed ratio, flow field design on single cell and feed distribution on stack of cells. The experiments were carried out by using two cells, one with serpentine flow field and the other with spiral flow field. These cells were fed with hydrogen and oxygen at low volumetric flow rates from 1 to 2 ml/sec and stoichiometric ratios of fuel (H2) to oxidant (O2) as 1:2, 1:1 and 2:1 respectively. The results showed that the highest voltage and efficiency can be obtained for the stoichiometric ratio of 1:2, while the ratio of 2:1 produced the lowest voltage and efficiency. Also the best results were obtained with the serpentine flow pattern after comparing with the spiral flow pattern in a single cell. Likewise it was proved that the voltage and efficiency are maximized when using the stoichiometry of 1:2, besides that the parallel feed connection of the stack of cells produced much power than the series connection.
This research includes the principles of the democracy، and to which extent it can contribute in establishing these principles. Democracy is not only to hold parliamentary or presidential elections but also the result of these elections wills it lead to the emergence of an integrated regime that can actually expresses the citizen's rights and to which extent those citizens can contribute in that regime and control it. Since 2005، when the first elections took place in Iraq after the US occupation of Iraq 2003، Iraqi people are looking to a rule that represented them and achieve their interests after getting rid of the totalitarian regimes and establishing an institutional regime that work by democratic means in order to achieve the so
... Show MoreThis research aims to examine the ability of impact of the cash flow statement indicators in the change in the market value of the industrial firms listed on the Palestine Stock Exchange. The research population consisted of (13) firms during the period (2015-2020). Data were collected from the annual financial statements of the firms. The research relies on the Pooled effects model to analyze the cross-section data (Panel Data), and the multiple regression method to test the hypotheses. The research finds a positive significant impact of (the ratios of cash flows from operating activities to sales, the return on assets from operating cash flows, and cash flows from operating activities to total current liabilities) in the change
... Show MoreThe splicing design of the existing road and the new road in the expansion project is an important part of the design work. Based on the analysis of the characteristics and the load effect of pavement structure on splicing, this paper points out that tensile crack or shear failure may occur at the splicing under the repeated action of the traffic load on the new/old pavement. According to the current structure design code of asphalt pavement in China, it is proposed that the horizontal tensile stress at the bottom of the splicing layer and the vertical shear stress at other layers of the splicing line should be controlled by adjusting the position and size of the excavated steps in addition to the conventional design ind
... Show MoreField experiments were carried out for the autumn season 2022- 2021 in the field of College of Agricultural Engineering Sciences - University of Baghdad - Jadiriyah Complex –Station A- to study a combination of organic fertilizer (Vermicompost) and cow manure as well as a control treatment (soil only) intertwined with Spraying with silicon, calcium and distilled water (control) in the growth and production of three cultivars of beet (Cylindra, Dark Red, Red) within the design of Completely Randomized Block Design at three replications, The number of treatments was 9 for each replicate. The means were compared according to the least significant difference (L.S.D) at a probability lev
In the Name of God, the Most Gracious, the Most Merciful
Praise be to God, who taught the pen anthropology unless he knows, and peace and blessings be upon the master of bullying, and the imam of the eloquent Prophet Muhammad, the sincere and faithful, and his family and companions as a whole and whoever followed him to the Day of Judgment. And after:
The science of grammar is among the most important of all language sciences at all, if not the most important of its sciences, due to the multiplicity of its doctrines and schools, the diversity of its methods, its phenomena and subjects, as well as the connection of this science with the most honorable languages,
The research aims to understand the psychological status of and the feeling of loneliness of the trainees (recently released detainees) participating in the training and rehabilitation courses held in the Technical College - Baghdad. The study was conducted on a specimen of (23) trainees. An open questionnaire was adopted which included one question that was ( What was your feeling psychologically and socially before taking part in the training course?) , also the feeling of loneliness Scale , designed by ( Russel,Peplau, Cutrona /University of California Los Angeles ) was implemented after the courses .
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... Show MoreAfter this systematic presentation of the phenomenon of rotation of formulas, ie the construction of the verb and the verb, and the narrated narratives therein differed among the readers, it became clear to us how the difference was clear between reading and the other, and how readers have varied in their readings of the verb, As we have noted through our modest research that the phenomenon of building the verb for the actor and the effect have included the act of both past and present tense, and not limited to a specific time, and this difference in reading was not limited to a particular environment, but beyond To more than one environment This is evidenced by the readings of various readers from the environment of Kufa, Basra, Mecca,
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Abstract This research deals with the definition of the concept of nodal purposes, And what is related to it, from its aim and importance, And for the purposes of the importance of Streptococcus In trying to understand the nodal truths For different minds, Especially with those who object to the introduction of belief in purposes studies, This research has two requirements: The first requirement: the concept and the aim of contractual purposes,It consists of two branches, The first is in the concept of nodal purposes, And it dealt with the definitions in terms of language and terminology And what we see is proportional to what aim |
The current research aims to know the complementary use of the paper book and the digital book by defining the paper book and the digital book and knowing the methods and methods of obtaining each of them and indicating the extent of their use and for what purpose and knowing the difficulties that researchers face in using each of them and which is better using the paper book or the digital book in preparing research Studies and for no reason. The research relied on the descriptive approach and the questionnaire as a tool for data collection, and it was distributed to professors and students of Iraqi universities. The research sample reached (219) individuals and reached a set of results, the most important of which are: Preference for the
... Show MoreHuman witnessed over the centuries many of the important issues faced by the international community was centered on human rights in general and the persecution of refugees, especially according to many forms may be directly or indirectly leaves behind economic crises, social and humanitarian push world countries to rethink the mechanisms and the feasibility of developing agreements and laws and the role of international and regional organizations to protect peoplerefugeestatus.